from tkinter import *

coords = [0, 0, 10, 0, 10, 10, 20, 10, 20, 20, 10, 20, 10, 30, 0, 30]                                            

root = Tk()
root.title("ИТ марафон")
root.geometry("500x500")

canvas = Canvas(bg="white" , width=500 , height=500)
canvas.pack(anchor=CENTER, expand=1)
canvas.create_polygon(coords)

root.mainloop()
